Why do I need a 'General Purpose' storage account for Azure?

A requirement we have however is to make use of a General Purpose storage account as opposed to cold storage for instance. We make use of this type of account due to the fact that general purpose account offers the use of (i)tables - which is something we need and (ii)costs.

Obviously cold blob storage accounts cost less than general purpose accounts for holding storage, however it is costlier when handling a lot of requests. Since Altaro VM Backup needs to request a lot of 128KB blocks during the backup operation it turns out that a General Purpose account is actually much more cost effective than using cold blob storage.